Colab (formerly Gangplank), which appears to be mostly oriented to computer, software, and robotics

Colab is on Pennington on the north side, right next to the Pioneer complex (maybe part of it). In a business district street-side office space, so there's no place for heavy anything, an ideal place for electronics and computer work. And parking in the Pennington Street Garage (which, of course, you pay for).

Xerocraft, which appears to be oriented to heavier stuff, as they offer classes in welding, lathe, milling, and that sort of thing.

Xerocraft is at the corner of 6th Street and 9th Avenue, right where the railroad crosses 6th. Very nice location, very appropriate for heavy machinery, in the Warehouse District. Much more appropriate than the kooky art galleries that occupy other former warehouses in the area.

Unfortunately, it seems that it costs to be in the Tucson Originals "club", and restaurants will drop out of it occasionally. Here are some places that used to be Originals, aren't anymore, but we've been to and liked them: